By the Riemann method, a coupled wave model is derived for the ordinary-to-ordinary (OO) and extraordinary-to-extraordinary (EE) Bragg diffraction of a Gaussian beam by overlapping holographic gratings in a uniaxial crystal. The computer simulation is used to discuss the relations among the diffraction efficiency, the index modulation, the wavelength sensitivity, the angular sensitivity, and the the widths of the recording and reading beams. The characteristics of EE and OO diffraction in a uniaxial crystal are found to be remarkably different. The simulation shows that EE diffraction may exhibit far higher diffraction efficiency than does OO diffraction for very low index modulation with the same hologram size, for example, nearly 90% when the size is 8.2×10^−5.
© 2005 Optical Society of America
(050.7330) Diffraction and gratings : Volume gratings
(090.7330) Holography : Volume gratings
(160.5320) Materials : Photorefractive materials
(260.1960) Physical optics : Diffraction theory
Hanming Guo, Jiabi Chen, Xiangning Li, and Songlin Zhuang, "Diffraction characteristics with various polarizations of overlapping holographic gratings in a uniaxial crystal," J. Opt. Soc. Am. A 22, 1834-1843 (2005)